Shellfish grown in Louisiana and along much of the United States coast face trouble in the future because the oceans are getting more acidic because an increasing amount of carbon dioxide is getting absorbed into the water, according to a new paper released Monday in Nature Climate Change.
In the Pacific Northwest, oyster growers have been dealing with this problem for several years, as the ocean acidification issue advanced more quickly because of upwelling currents off the coast.
As the change occurs, young oysters die because the acidic water hampers shell growth at its most vulnerable time.
“Ocean acidification has already cost the oyster industry in the U.S. Pacific Northwest nearly $110 million, and directly or indirectly jeopardized about 3,200 jobs,” the paper says.
Similar consequences could be felt in coastal areas around the United States in fishing and shellfish communities, said Sarah Cooley, science outreach manager at Ocean Conservancy and one of the report’s authors.
The paper looks at the vulnerability of shellfish industries around the country and provides possible suggestions on how to adapt to the changes. The changes range from diversifying the species grown in an area to hatchery management plans like some oyster growers in the Pacific Northwest are using.
In some areas of the Pacific Northwest oyster industry, oyster farmers depend on the oyster hatcheries to provide young oysters for placement. Some hatcheries are now testing any water that comes into the hatchery and, if needed, are adjusting the pH levels if the water is too acidic for oyster growth.
Co-written through collaboration between scientists at the Natural Resources Defense Council, the Ocean Conservancy, University of California at Davis and Duke University, the report looks at the human and economic side of the ocean acidification issue.
The potential impacts and severity of those impacts depend on numerous factors, including how much shellfish is harvested in an area, the diversity of the shellfish population and access to science experts, and information to address any problems, Cooley said.
Although the Gulf Coast doesn’t have the ocean upwelling that has brought the problem to Northwest shellfish growers, areas of low oxygen like the annual “dead zone” off the coast of Louisiana also can make the problem worse, she said.
Although the report wasn’t geared to look at when those types of effects could start being seen in the Gulf Coast region, other research in the form of computer models is on the way to help address that question.
“We don’t have those kinds of models for most areas of the coast right now,” she said, but there are plans to get them developed.
Another problem is there isn’t a lot of scientific instruments measure the ocean acidity levels yet.
“We don’t have enough observing capacity around the country and that is something NOAA (National Oceanic and Atmospheric Administration) is working very hard to improve,” Cooley said.
Follow Amy Wold on Twitter, @awold10.